I must, I must, I must work out my carbs...(warning - boring chunter follows)

Again, unless you're an Eighties' child, and, perhaps, more specifically, an Eighties' girl, who happened to read books by a certain author whose books saw a bit of a "craze", perhaps more specifically Judy Blume, and read a certain book by that author, perhaps more specifically, "Are you there God? It's me, Margaret", then you won't recognise the roots of that blog post title.

It's just me, isn't it?

Oh well, anyway, I must work out my carbs, having wasted the first part of my evening messing about on the internet and eating. So I thought I would combine the first of these things with the task-in-hand and try to work it all out in a blog post. Neat, huh?

So. They say (Them Wot Is In The Know) that during a marathon, you'll typically use up about 30-60g of carbs per hour. I need to work out how many gels I'll need, and how much Lucozade Sport I will need to glug at each of the Lucozade Sport stations - which are every 5 miles. Water stations are every mile, but we can discount those completely, because water has no carb value and I will probably run straight past most of these mile-stations (unless it's very hot). No hyponatraemia for me, thanks very much.

So. SIS gels are somewhat lighter than other gels, which gives them the advantage of being much more palatable and even refreshing. In the Forest of Dean Half, which was quite hot, they seemed really rather refreshing to me, anyway. However, this gives them the disadvantage of not containing as many carbs as other gels. Frankly, I'd rather have to consume the gels more frequently than be gagging and hacking after taking one and trying desperately to wash away the taste.

Each SIS gel contains 22g of CHO. Lucozade sport contains 6.6g CHO per 100ml, and, on the big day, is served up in 330ml bottles - so each one will contain around 22g of CHO. Ooooh, that's convenient. Now, in training, jogging along at a comfortable pace sipping Lucozade Sport frequently from my Camelbak and with gels in my belt, I've noticed feeling the need for a gel every three miles or so. Which would be about right - two gels per hour (just over, because I won't be able to keep 10min/mile dead up for 26 miles!!), plus some sippages of Lucozade, and I'll be well sorted. I should probably aim to drink most of a bottle of Lucozade in order to keep my fluid levels up, but I will probably opt more for sipping the Lucozade for about a mile, then abandoning it and getting some water from one of the stations. I don't like having a lot of stuff sloshing around inside of me whilst running, it just gets uncomfortable. On my last 20-miler, I just about finished off the entire capacity of my Camelbak over 3hrs 50 - 1.4l of Lucozade. Most people would probably say that's not enough fluid, and, certainly if it's very hot I'd need to take more, but that works for me. And I didn't feel unwell at the end of that run.

So, if I take a gel every three miles that'll be 3, 6, 9, 12, 15, 18, 21, and 24. Good, that'll be just perfect timing for the last gel to be fuelling the last mile or so. That means I'll need 8 gels. I'll be seeing my supporters at mile 15 and the RW supporters at mile 17, so I can leave gels with them for the last part of the race. So I'll need four in my belt to start with, have one off the "Support Dr Cath!!" crew at mile 15, and then I'll give the Mudchute crew three to give me at mile 17. Which is convenient, cos I think four is about the total capacity of the pouch on my belt!!

Did you get all that? Great. Now, can you explain it to me, please?